Living Environment Regents Practice Test 2025 - Free Regents Practice Questions and Study Guide

Mature red blood cells are unique because they undergo a process of development that involves the loss of their nuclei once they reach maturity. This loss is significant because the nucleus contains the genetic information needed for cell reproduction, including the processes of mitosis that allow for cellular division. As a result, mature red blood cells cannot reproduce themselves or create new copies, which is critical for cell generation and maintaining the population of cells in the body.

The other options are processes that mature red blood cells can still perform, albeit in a limited capacity due to their structural adaptations. Respiration refers to the process of obtaining oxygen and removing carbon dioxide, which red blood cells excel at by being filled with hemoglobin. Metabolism encompasses all the biochemical reactions that occur within cells, including energy production, which mature red blood cells can still carry out to some extent despite lacking a nucleus. Digestion, in a broad sense, involves the breakdown of substances for absorption, and while red blood cells do not perform digestion like other cells in the body, they play a role in transporting metabolic byproducts throughout the bloodstream.